The FDA has approved entecavir (Baraclude) for treating chronic hepatitis B virus (HBV) in adults. Previously, the only drugs approved for chronic HBV were lamivudine (Epivir-HBV), interferon-alpha 2b (Intron A), and adefovir (Hepsera).

Entecavir, which is taken orally, works by interfering with viral reproduction. Studies have shown that patients taking it have significant improvement in liver inflammation and fibrosis.

Side effects include headache, abdominal pain, diarrhea, fatigue, and dizziness. Because patients may experience severe worsening of HBV after stopping entecavir, those who discontinue the drug should have their liver function repeatedly and regularly monitored.

Source: U.S. Food & Drug Administration. "FDA approves new treatment for chronic hepatitis B." 2005. www.fda.gov/bbs/topics/ANSWERS/2005/ANS01348.html (22 Apr. 2005).